Prevalence and causes of anemia in elderly hospitalized patients

The prevalence and causes of anemia have been studied in 104 patients over 60 years of age admitted to a general medical ward in Jerusalem. In males and females, mean hemoglobin levels were about 1 g less than in the corresponding groups of healthy younger controls. A primary nutritional anemia could not be implicated in any of the 15 patients with hemoglobins below 11 g/dl. The most important causes of anemia were chronic renal failure, metastatic carcinoma, gastrointestinal bleeding, and infection. Conversely, in diseases with no adverse effect on erythropoiesis such as chronic ischemic heart disease, hypertension and diabetes, hemoglobin levels were equal to those of the younger controls. These findings indicate that although diminished serum iron and RBC folate levels may occasionally be found in elderly subjects, nutritional deficiency is seldom responsible for anemia in this age group in Israel- and anemia when present is often the manifestation of a chronic underlying disease.

Anatomical arrangement of muscle tissue in the anterior mitral leaflet in man

Muscle tissue in atrioventricular (A-V) cardiac valve leaflets was studied in 35 human hearts and was found to be more prominent in the anterior leaflet of the mitral (MAL) than in the other valve leaflets. From serial sectioning and wax model reconstruction, the anatomic arrangement of the muscle in the MAL indicates bundles passing from the two commissural regions towards the mid-zone of the valve. Age did not appear to reduce the mass of muscle tissue in the MAL. The possibility of muscle contraction in the MAL increasing leaflet tension and accelerating post-artial movements received support by comparisons of the anterior and posterior leaflets of the mitral valve in their movements towards closure.

Sea urchin nuclei use RNA polymerase II to transcribe discrete histone RNAs larger than messengers

RNA transcribed in isolated sea urchin nuclei and assayed by hybridization to histone genes cloned in E. coli contains sequences homologous to each of the five histone genes. Histone RNA is synthesized exclusively from the same DNA strand which is the template in vivo. Synthesis of the histone gene transcripts is sensitive to alpha-amanitin concentrations which inhibit RNA polymerase II activity. The fraction of histone RNA synthesized in vitro is comparable at two developmental stages to the fraction synthesized in vivo. The nuclear histone transcripts contain sequences homologous to spacer DNA regions present between the coding regions of the 6500 base pair (bp) histone gene repeat unit. The transcription of spacer sequences was demonstrated by hybridization of the nuclear transcripts to subcloned spacer DNA. Although the bulk of the RNA transcripts are greater than 2000 bases long, the histone-specific transcripts are of discrete sizes ranging from 100 bases to about 1100 bases long. Each histone gene hybridizes with at least one of the larger transcripts and with a different subset of smaller RNAs. We do not detect any giant polycistronic transcript spanning the entire histone repeat unit.

Identification of a C-Glucuronide of Dgr6-Tetrahydrocannabinol as a Mouse Liver Conjugate in vivo

Delta(6)-Tetrahydrocannabinol-C-4(')- glucuronide was found in the livers of mice that had been administered Delta(6)-tetrahydrocannabinol. Thus, C-glucuronidation of a compound that contains a free hydroxyl group has been demonstrated in vivo.

Identification of a C-glucuronide of delta6- tetrahydrocannabinol as a mouse liver conjugate in vivo

Delta 6-Tetrahydrocannabinol-C-4-glucuronide was found in the livers of mice that had been administered delta 6-tetrahydrocannabinol. Thus, C-glucuronidation of a compound that contains a free hydroxyl group has been demonstrated in vivo.

Cellular immunity in squamous cell carcinoma of the uterine cervix

The thymus-dependent immunity of 42 patients with SCCC was evaluated by: delayed cutaneous reactions to ubiquitous antigens, DNCB sensitization, and lymphocyte response to PHA. In addition, T and B lymphocytes were detected in peripheral blood and in tumor sections, by adherence to E and HEAC. Depressed CMI was more intense in patients with disseminated disease, although a premature impairment of CMI was observed in some patients with initial-stage tumors. The absolute number of peripheral T lymphocytes showed association with both cutaneous reactions and PHA response. However, there appeared to be no significant correlation between the stage of the tumor and the pattern of adherence of E or HEAC to the biopsies.

Electrostatic interactions among hydrophobic ions in lipid bilayer membranes

We have shown that the absorption of tetraphenylborate into black lipid membranes formed from either bacterial phosphatidylethanolamine or glycerolmonooleate produces concentration-dependent changes in the electrostatic potential between the membrane interior and the bulk aqueous phases. These potential changes were studied by a variety of techniques: voltage clamp, charge pulse, and "probe" measurements on black lipid membranes; electrophroetic mobility measurements on phospholipid vesicles; and surface potential measurements on phospholipid monolayers. The magnitude of the potential changes indicates that tetraphenylborate absorbs into a region of the membrane with a low dielectric constant, where it produces substantial boundary potentials, as first suggested by Markin et al. (1971). Many features of our data can be explained by a simple three-capacitor model, which we develop in a self-consistent manner. Some discrepancies between our data and the simple model suggest that discrete charge phenomena may be important within these thin membranes.

[In vitro malignant transformation of fetal hamster brain cells by methylnitrosourea]

Using primary cultures originating from 14 day old fetal Hamster brain, we have obtained a cell line with glial morphology. These cell remain non transplantable during the first year of in vitro culture, but undergo spontaneous transformation during the second year. Following prolonged contact of the glial-like cells with 25 to 50 microgram/ml of methylnitrosourea (MNU), a malignant transformation is observed 5 months after the treatment. The lowest concentrations of (MNU) do not cause malignant transformation, but seem to inhibit (or postpone) the spontaneous transformation. After MNU treatment, cells retain their glial nature.

Hamster cells, untreated and treated with chemical carcinogens, maintained in vitro for 2 1/2 years

We have maintained in culture, for a prolonged period, untreated hamster cells from whole embryo, foetal brain and lung from newborn animals. Among the 7 lines studied we observed only one spontaneous transformation during the first year of culture. The cells of the 6 other control lines remained normal and diploid, and were not transplantable during the first 9 to 12 months of culture. After the 12th month, changes appeared in their in vitro behaviour and their transplantability: grafts of 0-5-2 X 10(6) cells induced tumours in the hamster; fewer cells did not. In vitro chemically transformed hamster cells were fundamentally different from untreated cells of the same origin, not only in morphological and growth characteristics but also in transplantability; of the 9 lines obtained, 7 induced tumours after injection of 10(1)-10(4) cells, and 2 after injection of 10(5) cells per animal.

[Study of the antibody-dependent lymphocytotoxicity test as a function of the nature of the antibodies]

It is well known that IgM antibodies are inactive for the LDA test. Moreover, this work showed 7 S IgM to be just as inactive as 19 S IgM. With HLA antibodies, usually IgG, this work showed that the LDA test was not inhibited by a temperature of + 15 instead of + 37 degrees C. With cold lymphocytotoxic antibodies 19 S and 7 S IgM the LDA test was negative even at + 15 degrees C (optimum temperature for these complement dependant lymphocytotoxic antibodies) with or without prolonged incubation. Under these same conditions, a negative result was obtained using auto-lymphocytes as a target. Finally, our results confirmed that IgM antibodies with anti-HLA activity could not act as mediators even for targets with corresponding HLA activity.

Localization of T and B lymphocytes in human adenoid, tonsil, appendix and Peyer's patches

T and B lymphocytes were detected in human adenoid, tonsil, appendix and Peyer's patches by adherence to sheep erythrocytes (E) and human erythrocytes sensitized with antibody and complement (HEAC). The percentages of T lymphocytes in adenoid and tonsil cell suspensions averaged 30.9 +/- 3.4 (S.D.) and 35.8 +/- 6.4 (S.D.). The percentages of B lymphocytes in the same tissues were 42.5 +/- 11.3 (S.D.) and 40.1 +/- 34 (S.D.) respectively. In adenoid and tonsil tissue sections, B lymphocytes were found in the follicles and T lymphocytes were detected around the follicular areas. The predominant cell population in Peyer's patches and appendix sections was constituted by B lymphocytes.

Biosynthesis and stability of globin mRNA in cultured erythroleukemic Friend cells

Biosynthesis and stability of the mRNA population in DMSO-induced Friend erythroleukemic cells were studied after labeling the RNA with 3H-uridine and then chasing it with nonlabeled uridine. Globin RNA metabolism was studied by hybridization to excess complementary DNA convalently coupled to oligo(dT)-cellulose. After a labeling period of 120 min, 2-4% of the poly(A)-containing labeled RNA was in globin RNA; it decayed with a half-life of 16-17 hr. The rest of the poly(A)-containing RNA was composed to two kinetic populations: 85-90% decayed with a half-life of about 3 hr, while 10% decayed with a half-life of about 37 hr. The portion of globin RNA in labeled poly(A)-containing RNA behaved in an unexpected fashion during the chase period. During the initial chase period, the percentage of globin RNA increased rapidly, reaching a maximum of about 15% at 20 hr, but it subsequently declined gradually. Based on these findings, a model was built that describes the changes in the proportion of globin mRNA in poly(A)-containing RNA during continuous synthesis and after chase of the labeled RNA. It appears that if the parameters described remain constant during the maturation of erythroblasts, then this model would not account for the almost exclusive presence of globin RNA in the reticulocyte. By far the most effective way to achieve this high level of globin RNA is the destabilization of the mRNA population which is more stable than globin RNA, and not the stabilization of globin RNA itself.

Quantitation of labeled globin messenger RNA by hybridization with excess complementary DNA covalently bound to cellulose

A method is described to quantitate labeled globin mRNA by hybridization with excess cDNA which was enzymatically polymerized on oligo(dT)-cellulose. In a large excess of cDNA-cellulose the rate of RNA hybridization was dependent on DNA concentration and not on RNA concentration. Nonhybridized RNA can be digested by RNase and washed from the cDNA which is covalently bound to cellulose. This enables the detection of labeled globin mRNA even when present in a porportion as low as 0.02-0.03% of the total RNA.